Medichecks Blood tests - are they always accurate?

[HKAnne]

Good morning all,

I was a bit concerned with my latest Medicheck blood tests below:

Test taken in March 2019 taking 75ug & 100ug Levothyroxine on alternate days plus 13.50ug T3

TSH 0.032 (0.27-4.2)

Free Thyroxine: 20 (12-22)

Free T3: 6.75 (3.1-6.8)

and

Test taken in May 2019, taking 75ug levothyroxine plus 6.75ug T3

TSH: 0.222 (0.27-4.2)

Free Thyroxine: 23.300 (12-22)

Free T3: 6.69 (3.1-6.8)

I'm just surprised that after reducing my T3 for eight weeks my recent tests don't look right. I was expecting TSH to go up and Free Thyroxine to go down slightly.

Many thanks.

[Judithdalston]

Your TSH has gone up by almost x8, the FT3 has gone down slightly, but your FT4 has risen too. Did you have a proven need, eg low T4 conversion, for adding T3?

[HKAnne in reply to Judithdalston]

Sorry, I got my ups and downs muddled meant to say FT3 down and FT4 risen. Yes, I do have a proven need for T3.

[SlowDragon Administrator]

Your vitamin levels may have dropped with dose reduction. This can reduce conversion of FT4 to FT3

[HKAnne in reply to SlowDragon]

Thanks Slowdragon. All my vitamin levels were looking good on the last blood test.

[SlowDragon Administrator in reply to HKAnne]

But when we reduce dose conversion often gets worse.......certainly initially

You may need to wait at least 12 weeks for everything to settle

Do you feel better on lower dose?

[HKAnne in reply to SlowDragon]

I felt "wonderful" on the higher dose. I usually notice the difference fairly quickly after an increase/decrease in medication. It has been just over 10 weeks since my reduction.

[radd in reply to HKAnne]

HKAnne,

Except for meds dose reduction, were both tests done exactly like for like ?

[HKAnne in reply to radd]

Hi Radd

Yes, exactly the same

[radd in reply to HKAnne]

HKAnne,

I would have expected a higher TSH & much reduced FT3 on the latest test as you halved your T3 med dose eight weeks ago.

TSH is variable and FT4 levels are commonly seen to reduce with medicated T3 so these results wouldn’t concern me.

But the second FT3 result is still quite high and if blood was drawn 8-12 hours after your last med dose, your T3 peaks would be taking you over range.

[HKAnne in reply to radd]

Thanks Radd, blood was drawn 24 hours after my last med dose. I am not due to go back to the Endocrinologist until the end of October, so it will be interesting to see how my bloods are looking then

[SeasideSusie Remembering]

When were your last doses of Levo and T3 before these tests?

It's advised to take last dose of Levo 24 hours before test and last dose of T3 8-12 hours before test.

[HKAnne in reply to SeasideSusie]

Hi SeasideSusie,

Many thanks for your reply. I take my levothyroxine and T3 once per day, one hour before breakfast. My blood test was taken 24 hours after levo and T3. My Endo. has told me not to take T3 during the day/evening as I would have trouble sleeping.

[SeasideSusie Remembering in reply to HKAnne]

As you left 24 hours between last dose of T3 and blood test, then your FT3 result is showing a false low and the normal cirulating hormone level will be higher than that shown.

I take Levo plus T3 and normally take them both together in the early hours of the morning when I visit the bathroom. What I tend to do, for just the one day, on the day before my test I alter the timing and take Levo at 9am (I know I will do test at 8.30am the next day) with half my T3 dose, then I take the other half of my T3 dose between 9pm and bedtime. Then immediately after the test I take both my Levo and T3 in one dose.

My Endo. has told me not to take T3 during the day/evening as I would have trouble sleeping.

Have you actually tried this and it disturbed your sleep, or is this just something your endo has said? Many people find they need their T3 split into 2 or 3 doses divided equally during the day, some take an evening/bedtime dose. If this is just something your endo has said then ignore it until you've tried it yourself and then make up your own mind.

Bearing in mind that you have Hashi's, it looks like these results are showing a bit of a hyper-swing and you could possibly do with reducing your Levo and T3 a bit for now and readjust dose when things settle down again.

[HKAnne in reply to SeasideSusie]

Thanks SeasideSusie. I will try taking my T3 tomorrow night instead of in the morning. I do have problems sleeping, so perhaps this will help. It would be hard for me to split the T3 dose as I am only taking quarter of a tablet once per day.

For my next blood test, I will take your advice and try taking T3 12 hours before blood test, I already take levo 24 hours before tests.

[SlowDragon Administrator in reply to HKAnne]

Endo is clueless then.

Many of us take T3 as split dose and find taking last T3 dose at bedtime dramatically improves sleep

Suggest you might try it

If/when also on T3, make sure to take last dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test

[HKAnne in reply to SlowDragon]

Hi SlowDragon,

Thanks for this information, I will definitely try taking T3 at bedtime tomorrow.

I will also take your advice on taking T3 8-12 hours before next blood test.